Michael Cohen, former US President Donald Trump's personal lawyer and fixer, is scheduled to appear Monday before a Manhattan grand jury investigating hush-money payments made on the former President's behalf, AP reported citing two people familiar with the issue.

Cohen is a major witness in Manhattan District Attorney Alvin Bragg's investigation, and his testimony comes at a pivotal time as prosecutors consider whether to charge Trump. It is worth noting that prosecutors may save their most crucial witnesses until the very end of a grand jury inquiry.

In recent weeks, Cohen has been with Manhattan prosecutors on a regular basis, including a day-long session on Friday to prepare for his appearance before the grand jury, which has been hearing evidence in the case since January.

Cohen declined to speak to reporters as he exited the meeting, saying he'd be "taking a little bit of time now to be silent and let the D.A. to build their case," AP reported.

Trump continued to slander the investigation on social media on Friday, calling it a "scam, injustice, slander, and complete and total weaponization of law enforcement in attempt to influence a Presidential Election!"

This week, a New York grand jury invited former US President Donald Trump as part of the Manhattan district attorney office's investigation into hush money payments made to Stormy Daniels, an adult film actress whose real name is Stephanie Gregory Clifford.

Michael Cohen, the former attorney in charge of the Trump case, had pleaded guilty in 2018 on federal charges concerning offering Clifford $130,000 as hush money after she claimed she had an affair with Trump, who in turn denies.

It is important to note that it's not prohibited to pay someone hush money in the US. 

However, authorities are considering whether to prosecute Trump for falsifying the Trump Organization's financial records in relation to how they recorded the reimbursement of the payment that Michael Cohen, his then-fixer claimed to have provided to Daniels. Cohen received $360,000 in salary plus a $60,000 bonus for a total of $420,000 back in 2018.

During Cohen's criminal case, federal prosecutors stated that Trump was aware of the payments to the women. But, the US Attorney's Office in New York declined to file a criminal complaint against the then-President.

Cohen, who is now estranged from Trump, has talked with prosecutors 20 times throughout the course of the hush-money investigation. In January, he handed over his cell phones to Manhattan prosecutors so that they could collect evidence, including voice recordings of talks he had with Daniels's lawyer, Stephanie Clifford, as well as emails and text messages.

Several members of Trump's closest circle, including his former political adviser Kellyanne Conway and former spokesperson Hope Hicks, have met with Manhattan prosecutors in recent weeks.

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